SparkFun Electronics Commentsurn:uuid:214d0e4e-f1b1-d287-ce26-ac5b4c9f82492016-12-09T08:23:42-07:00SparkFun ElectronicsCustomer #744395 on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Customer #744395urn:uuid:f1b6e604-0f56-8989-9150-20a236b442002016-08-24T15:35:59-06:00<p>The data sheet wires the left and right channel from the audio into the msgeq7 with 2 22k resistors for each channel into the .01uF(10nF) capacitor then into the Audio In pin but I&rsquo;ve seen other people hook it up with the capacitor only either 10nF or 1nF. what is the difference between using the 22k resistors+capacitor vs the capacitor only? and also is there a benefit when it comes to output readings when using 1 msgeq7 for mono or using 2 msgeq7&rsquo;s for stereo reading left and right independently? thank you to anyone who responds :)</p>Eliot2 Electric Boogaloo on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Eliot2 Electric Boogaloourn:uuid:06ba0e1a-cb8d-0a59-5862-cbd0d40d836b2015-10-12T12:41:49-06:00<p>Anyone use this at 3.3V? I&rsquo;ve got it connected to BOB-09964 but it seems completely unusable at that voltage. I&rsquo;m testing on an Arduino but want to eventually switch to an ESP8266.</p>The Doctor Doge on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7The Doctor Dogeurn:uuid:13a0ce10-8338-0fc4-0e18-44b40462e6812015-07-27T16:00:06-06:00<p>Can the multiplexer be controlled without the reset pin if I just want to cycle thru all of them?</p>Customer #504746 on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Customer #504746urn:uuid:158730f4-825e-21d2-eb55-0ffdfe0a491e2015-05-06T19:01:08-06:00<p>Any ETA on this? Bought ~20 from EBay, shipped from China. Nearly all of them are defective. Lots of noise or simply DoA.</p>Customer #504746 on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Customer #504746urn:uuid:e9459f3d-07db-5c86-e694-05d546efd1672015-05-06T19:00:04-06:00<p>This is still true in 2015. 7 out of 10 chips are defective. All from eBay.</p>404NotFound on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7404NotFoundurn:uuid:aa4aa7f1-7b51-bf77-fad4-f5a27e4ad2082014-12-04T17:54:35-07:00<p>i&rsquo;m reading through the datasheet and description, and i m getting a bit confused.</p>
<ol>
<li>is the output a steady dc output at a certain level or does it oscillate.</li>
<li>can you lock the frequency it responds two or does it have to cycle between them.</li>
</ol>
<p>Thanks
-Joshua</p>Chiel on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Chielurn:uuid:9b81175c-a44e-188a-a247-70f54f082d052014-11-07T15:26:44-07:00<p>The MSGEQ7 has a high input impedance. It doesn&rsquo;t take the entire signal. it merely samples it. You can pass the signal to a different part with the chip merely being connected by its 1000pf capacitors to the signal.</p>
<p>Take a look at the &ldquo;Spectrum shield&rdquo; here on SF. its a arduino shield that does pretty much what you request. Its schematic should show how easy it is to use this chip!</p>Customer #385542 on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Customer #385542urn:uuid:1eeae05a-75be-fbe2-7c58-b1347bff74c42014-10-09T09:04:14-06:00<p>Mixed-Signal integration verified that there would be no problems shifting the range.</p>
<p>&ldquo;The formula is:
fo=1/(R*C) Hz</p>
<p>The clock to corners are:</p>
<p>Filter 1: 2620:1
Filter 2: 1030:1
Filter 3; 410:1
Filter 4: 156:1
Filter 5: 66:1
Filter 6: 26:1
Filter 7: 10:1"</p>
<p>I&rsquo;d like to try interleaving two chips for more total bands, I&rsquo;ll be curious to see if it is noticeable, or if the bands overlap so much it won&rsquo;t be useful.</p>Customer #385542 on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Customer #385542urn:uuid:1fae0cc4-4051-6e9f-3765-dbd5e77826da2014-10-02T09:03:08-06:00<p>I had good luck with this chip by running the input from my 3.3v powered electrete microphone through an op amp set up as a unity buffer, and then through a second set up as a log amplifier (pair of diodes between output and inverting input) to implement kind of auto gain control. Make sure to use an op-amp that can go rail-to-rail and play nice with low voltages. Try various types of diodes to change the volume gain curve. Then in software I implemented auto muting and un-muting of channels so little pops wouldn&rsquo;t show up occasionally, combined the data from the upper two channels since my microphone did not capture much high frequency, and added some additional level normalization. Next time around I want to try a microphone with AGC built in, and see if that is easier.</p>
<p>Here is my code and schematics:
https://github.com/Swap-File/tron-suit/tree/master/Jacket</p>Customer #589913 on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Customer #589913urn:uuid:522fe30a-adef-ecd8-2bb7-a47cd5d6025f2014-08-31T22:58:31-06:00<p>How can I still listen to music from the same audio source, when I already have it connected to this chip?
(How can hear the song at the same time the song is been processed by this chip?) What parts do I need for that?</p>Single T on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Single Turn:uuid:5e71886c-e51b-e874-a389-73e092f31a1a2014-06-20T10:59:41-06:00<blockquote><p>http://tronixstuff.wordpress.com/2013/01/31/tutorial-arduino-and-the-msgeq7-spectrum-analyzer/</p></blockquote>
<p>Hi, Have you tried the code found in this tutorial? Since you have 2 units that are both acting incorrectly, it is likely a code error.
Thanks</p>Customer #560636 on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Customer #560636urn:uuid:378c474e-b6af-d507-99c9-0cc63df8f37a2014-06-19T20:15:45-06:00<p>I have a problem with my set up. I have followed the spec sheet circuit, and hooked it to an arduino with code from http://nuewire.com/info-archive/msgeq7-by-j-skoba/
(I added the following lines to the void loop to bring the numbers down a bit):
int PWMvalue = map(analogPin, 0, 1024, 0, 255); // scale analogRead&rsquo;s value to Write&rsquo;s 255 max
if (PWMvalue &lt; 50)
PWMvalue = PWMvalue / 2;</p>
<p>The problem is that I am getting readings that are all over the map, regardless of the presence of an audio source. Here are a few lines from the serial readout without audio:
99 0 255 415 185 267 129
73 0 201 361 185 129 115
129 320 441 376 413 369 281</p>
<p>Is there a problem with my chip, the circuit, or the code? I&rsquo;m a bit at wits end here.</p>
<p>Thanks!</p>Customer #155501 on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Customer #155501urn:uuid:bada0388-7ed8-8090-ab21-e1b955fc79fd2014-05-07T18:42:41-06:00<p>Yes. There&rsquo;s an oscillator clock pin (8)</p>
<p>By varying the 200kohm resistor and 33pf capacitor, you can achieve different oscillator timings for the bandpass filters, essentially shifting the detection/filter range down/up.</p>Customer #513514 on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Customer #513514urn:uuid:1aa6eabf-bedf-b525-ca17-528b866280d22014-01-26T13:17:00-07:00<p>just a warning: don&rsquo;t buy these chips on ebay even though those are cheaper. I bought two and they were both defective. Each channel was broke (tons and tons of noise, completely unusable).
Someone else had the same problem, so my guess is that an ebay vendor (or a few of them) is selling defective chips. at any rate, stay away from them. I wasted days trying to troubleshoot them.</p>Customer #513514 on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Customer #513514urn:uuid:7b0d9c79-a584-f2f4-0932-28199dcef03e2014-01-26T13:12:32-07:00<p>I second this. The 2 chips I ordered from ebay had ridiculous amounts of noise on each channel that made them completely useless, despite adding noise filter caps. Both chips had the same problem. I spent days trying to get them to work.
Anyway, I realized what happened thanks to your comment. I bought 2 new chips from sparkfun after reading this. Hopefully they&rsquo;ll work much better than the ebay ones -_-</p>Customer #369574 on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Customer #369574urn:uuid:89e712d3-949b-e9eb-de6f-b43ff4698b762013-10-23T14:17:12-06:00<p>Is the MSGEQ7 DIP package eagle part available in the sparkfun libraries? I found a MSGEQ7 but I am not sure if it is surface mount of DIP.</p>Customer #44727 on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Customer #44727urn:uuid:839596d3-b38b-67cf-f340-7e87e9cf9dfe2013-05-31T07:42:19-06:00<p>I&rsquo;m trying to hoop up the msgeq7 to electret microphone (I&rsquo;ve tried both sparkfun&rsquo;s adafruit&rsquo;s microphones).</p>
<p>I&rsquo;m hooking it up as follows:</p>
<p>Pin 1 - 5v (.10uf between pin 1&amp;2)
Pin 2 - Gnd
Pin 3 - A0 (Arduino)
Pin 4 - D4 (Arduino)
Pin 5 - .1uf cap to OUT/AUD of the electret microphone
Pin 6 - .10uf cap to GND
Pin 7 - D5 (Adruino)
Pin 8 - through two 100kohm resisters to power, 33pf cap to 5v</p>
<p>I&rsquo;m getting numbers from 40-200 on channel 0 and 6 and number around 830-930 on channels 1-5.</p>
<p>that seems pretty constant regardless of my music volume</p>
<p>Any clues?</p>Toni_K on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Toni_Kurn:uuid:6c0a2fab-4193-5cd2-bb25-c12df922f3462013-02-19T11:37:50-07:00<p>As always, another great tutorial. Thanks for sharing!</p>JohnBoxall on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7JohnBoxallurn:uuid:6ae628c8-425e-8bb1-e029-822b5dff8ef02013-01-30T22:08:25-07:00<p>Wrote a tutorial that may be of interest: http://tronixstuff.wordpress.com/2013/01/31/tutorial-arduino-and-the-msgeq7-spectrum-analyzer/</p>Customer #385542 on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Customer #385542urn:uuid:e3cba09d-b5d4-8ab6-2707-c9d89b7686d72012-12-27T08:34:03-07:00<p>Note: The MSGEQ7 chips I ordered from eBay were all defective, replacements from sparkfun worked perfectly. Be careful, or you might waste time troubleshooting defective chips!</p>Customer #385542 on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Customer #385542urn:uuid:957629c8-e5ed-ed26-f522-3469f977628d2012-12-03T07:07:35-07:00<p>When using a 200k resistor and 33pf capacitor to select the oscillator frequency, what frequency should I be measuring on pin 8? Would I see 165khz like specified in the datasheet? Or is that frequency only present somewhere else internally on the chip?</p>Customer #245213 on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Customer #245213urn:uuid:cdb1c8a8-e495-631c-99c4-a56a6ca905822012-10-26T13:22:06-06:00<p>Where can I find this in a smd package?</p>Mike34 on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Mike34urn:uuid:b23f5a14-48c7-abb9-b404-9c64263048282012-08-31T22:09:19-06:00<p>That&rsquo;s exactly what I was thinking when I saw the old data sheet I thought to myself &ldquo;that .01 uf cap is probably gonna clip my bass response a little.&rdquo; So I decided I would use use a .1uf when the time came. Then here I see your post and I go look at the new datasheet and lo and behold! They read my mind!</p>war_spigot on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7war_spigoturn:uuid:cf0e378d-504c-c5c7-4074-ce491df886112012-04-05T15:35:07-06:00<p>Put it in stock literally the day after I bought it from eBay. Too bad for you guys I guess :(.</p>Nachos grande on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Nachos grandeurn:uuid:ab403e6f-3a4a-abc9-8288-71a80fc963c92012-01-15T12:51:30-07:00<p>can you change the frequencies this chip detects?</p>RIchardBoyd on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7RIchardBoydurn:uuid:ec421211-5765-ee4a-6143-5963661ec7a02011-10-26T15:47:56-06:00<p>Does anybody know how to run this off 3.3V? Every schematic I can find has 5V for VCC.</p>kylehotchkiss on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7kylehotchkissurn:uuid:0851521c-b897-55c1-0ed5-0beb2ffca6922011-10-15T19:27:02-06:00<p>I made a project with this. Got it onto <a href="http://hackaday.com/2011/10/15/christmasqualizer-is-the-next-light-switch-rave/" rel="nofollow" >Hack a Day</a><br/>
=)</p>Aristarco on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Aristarcourn:uuid:825c64d1-0ef8-b80a-4121-82baa69285bf2011-08-09T12:55:09-06:00<p>No need to drive separate LM3916s. Just use one and a multiplexed 10x7 display (or two 5x7 dot matrix modules) with the anodes driven by a decoder. This is the same method used in the now (sadly) discontinued Velleman Spectrum Analyzer Kit. One bargraph driver and a 1-of-10 decoder (in that design, a CMOS 4017 decade counter). Less parts.<br/>
But still, the design is complex with passive ICs only (no-microcontroller.)</p>willnue on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7willnueurn:uuid:d7f88e74-57b1-0fb3-8139-6a1d8be35bd02011-07-28T00:03:14-06:00<p>The link to the MSGEQ7 tutorial created by J Skoba is broken, but I have posted a copy on my site at:<br/>
<a href="http://nuewire.com/info-archive/msgeq7-by-j-skoba/" rel="nofollow" >http://nuewire.com/info-archive/msgeq7-by-j-skoba/</a></p>MDG on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7MDGurn:uuid:3ea13ef4-187a-d805-e9d6-9f95b6113c1b2011-07-20T19:09:27-06:00<p>Is the datasheet here outdated? This is the latest one from the Product Page: http://www.mix-sig.com/datasheets/MSGEQ7.pdf<br/>
The capacitor that should be on the input pin is now 0.1uF as opposed to 0.01uF?</p>WayneGnarlie on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7WayneGnarlieurn:uuid:8616921d-0b80-0bdf-4719-ede34aee6de62011-06-17T18:02:12-06:00<p>I&rsquo;ve been playing with these and yes you should be able to drive the LM3914 series of chips OK. Each output is fairly linear over 25db. But be aware that the output is refenced at around 500mv, so for best results use an rail to rail opamp to ground reference the output. You would connect the output of the MSGE7 to the positive input of the op amp. Place a 1K resistor from opamp output to negative input. Then connect a 50K pot from negative input to +5V, adjust pot for 0 volts out with no audio input to the MSGE7.<br/>
If you want to run standalone (no micro), things become complicated. You would need to use an analog switch to demux the output into seven outputs. Each output would drive a separate LM3916. This would require a 1 of 8 decoder to drive the analog switch and a divide by seven counter circuit to drive the 1 of 8 decoder (eighth output is not used). The counter would divide the strobe pulses from the timer.<br/>
The timer which drives both the counter and the MSGE7 strobe input could be a LM555. To avoid flicker, set the timer to produce a low duty cycle positive pulse. To adjust decay of display adjust the timer frequency higher for faster decay.</p>atypic on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7atypicurn:uuid:b7521b20-f47b-abc3-34ad-0a8d1a0083a92011-05-29T23:24:14-06:00<p>If I wanted to use this in an analog audio spectrum display, sending the voltages for each frequency band to power 7 LEDs for example, is there a demultiplexer I could use, instead of reading the values with an Arduino?</p>MechCD on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7MechCDurn:uuid:53483746-3d2f-d1b9-f9e0-15d1415364462011-05-15T20:59:41-06:00<p>What&rsquo;s a &ldquo;DC representation of the amplitude&rdquo;? An analog DC voltage between VDD and VSS? That datasheet is pretty rough.<br/>
It looks like this would work great with a set of LM3916s and a demux to make a simple spectrum analyzer</p>Toni_K on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Toni_Kurn:uuid:e4e156f5-edd1-994f-8921-7c0239d084ef2011-04-28T11:10:17-06:00<p>This new package is RoHS compliant, while the old one wasn&rsquo;t. You can still see the comments on the old product page, linked to above.</p>Nadeem on COM-10468 - Graphic Equalizer Display Filter - MSGEQ7Nadeemurn:uuid:2e2fe966-b723-3fd5-d28a-5828f59f7bdb2011-04-18T13:56:44-06:00<p>This listing is same as COM-10024 which is marked as retired now. What gives? We just lost those 14 comments.</p>